The present invention generally relates to a device for controlling at least one attachment.
This device can involve e.g. an excavator with a digging tool, e.g. a backhoe combination, attached to its boom.
Excavators with booms including a base boom articulated at the vehicle, an intermediate boom, and a handle carrying a digging tool are known from European Patent 0318 271 A1 and German Patent 38 43 753 A1. All parts of the boom are connected with one another via hinge points. In addition, either the base boom is rotatable relative to the vehicle around a horizontal axis or the intermediate boom is articulated so as to be rotatable relative to the base boom via a pivot connection whose axis extends substantially in the longitudinal direction of the base boom.
Excavators with booms whose respective excavator arm includes a base boom which can be constructed so as to be straight or angled and a handle carrying a digging tool are known from French Patent 2 333 416, U.S. Pat. No. 3,463,336, U.S. Pat. No. 4,274,797 and Japan Patent 56-95637. The base boom and handle are connected with one another via an articulation or joint whose swiveling axis is oriented vertically relative to a plane defined by the handle and the base boom. Moreover, pivot connections are provided in the structure of the boom according to which the handle is rotatable relative to the base boom around an axis which is arranged so as to be fixed with respect to the base boom at which the handle is rotatable around an axis extending substantially in the direction of the longitudinal axis of the handle, or the base boom is rotatable relative to the vehicle around a vertically extending axis which is fixed with respect to the vehicle, or the base boom is constructed in two parts, with one part which carries the handle being rotatable relative to the other part around an axis extending in the direction of the longitudinal axis of the latter part of the base boom.
An excavator with a boom whose excavator arm includes a base Boom, an intermediate boom, and a handle carrying a digging tool is known from German Patent 31 42 100. The base boom is constructed in two parts and the part of the base boom facing the intermediate boom is articulated at both sides via pivot connections so that the intermediate boom and the handle are swivelable in a plane extending parallel to the longitudinal axis of the vehicle.
An articulation of the intermediate boom of an excavator boom at the base boom is known from DE-OS 21 53 468. In this case, the intermediate boom is swivelable relative to the base boom, around two axes which are vertical relative to one another.
Finally, an excavator boom with a telescoping handle is known from "CONSTRUCTION" [DIE BAUWIRTSCHAFT], issue 33, Aug. 12, 1971, page 1158.
A characteristic of all of these excavator booms consists in an articulated construction of the boom adapted to the respective specific purpose, possibly with the additional use of a pivot connection. These booms accomplish the tasks imposed on them. However, problems arise when conversion is required corresponding to a different type of digging tool and an increased movability of the end point of the boom carrying the tool relative to the vehicle is necessary.